When coupling a supply voltage source to a load, a converter is sometimes used to condition the input voltage (e.g., 3-phase AC voltage) to produce an output voltage having the desired frequency and amplitude. Examples of these converters include voltage-link and current-link converters. In conventional converters, the AC input voltage is first converted to DC, which is used to synthesize the AC output voltage of desirable frequency and amplitude. These conventional converters typically require large internal capacitance.
A recently developed type of converter is the matrix converter, which is a solid-state device. Matrix converters provide a direct link between the input voltage and the output voltage without any intermediate energy-storage element. For example, in matrix converters, the large, internal energy storage elements (i.e., capacitors) are avoided, and an output AC voltage of any desirable frequency can be obtained from an input AC voltage of any frequency by using nine bi-directional switches for 3-phase input and output voltages.
Compared to voltage-link and current-link converters, matrix converters can be much more susceptible to the input voltage disturbances.